The red number on the top right corner of the app icon stays even when there are no more turns waiting. I'm experiencing this issue on a Huawei Mate 10 Pro running Android 10.
Sometimes the notification icon will clear, or the number will increase when there are more games, but most of the time the number is not correct. This means that the number of online games waiting do not correspond to the number in the icon.
Here is an illustration of the icon:

Does anyone else experience this issue? Is there anything that can be done to correct it?